The present invention relates to an improved check valve for use in a pressure balance faucet. It is mainly made up of a control valve body, a check valve block, a pair of positioning pins, two seal rings, a pair check valve sets and a valve mount. The check valve sets are secured to the check valve block which is housed between the check valve body and the valve mount that are in threaded engagement with each other. As the valve sets are worn out, they can be easily and quickly replaced by first dismantling the control valve body from the valve mount and then the check valve block being picked out by pincers to get the valve sets replaced with ease, speed in a DIY manner.
Referring to FIG. 1, a conventional check valve for use in a faucet is mainly made up of a valve body 10 and a pair of check valve sets 20. The valve body 10 is a hollow housing with a water discharge control handle at the top and is equipped with a hot and cold water pipeline connector 11 at the right and left side of its bottom. The connectors 11 are provided with inner threads 12 respectively. To the top and bottom of the valve body 10 is symmetrically coupled a water outlet duct 13. Each check valve set 20 has a connecting pipe 21 and a check valve 22. The connecting pipe 21 is hollow tube and has an externally threaded section 212 at each end. The check valve 22 has a hollow mounting seat 221 which is provided with a through hole 222 at the center of one end with a plurality of ribs outside the through hole. A spiral spring 223 is disposed in alignment with the through hole 222 and has a valve rod 224 engaged with the center thereof and led through the through hole 222. The valve rod 224 has one large step-like end to prevent the same from disengaging from the mounting seat 221 which is wrapped with a sleeve 225. Inside the sleeve 225 the mounting seat 221 can be rotated. A seal ring 226 is attached to the right end of the sleeve 225.
Such a prior art check valve structure has a following disadvantage in use: The mounting seat 221, sleeve 225 and seal ring 226 are made of rubber or plastics, and they will become hardened or shrunk after long period of use. The check valves 22 are easily out of function as the spring 224 is in fatigue. The check valves 22 of the check valve sets 20 must be replaced with the wall 30 partially removed, and the wall 30 must be repaired later the replacement. The cost of such a replacement is too high to be acceptable and the time is wasted.
The primary object of the present invention is to provide an improved check valve for use in a pressure balance faucet whose worn out parts can be easily and quickly replaced without structural damage of the wall around the fixed faucet.
Another object of the present invention is to provide an improved check valve for use in a pressure balance faucet wherein the check valve can effectively stop reverse flow of hot or cold water by way of a spring biased valve rod which can seal a stop hole of a sleeve of the check valve.